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diff --git a/elki/src/main/java/de/lmu/ifi/dbs/elki/utilities/scaling/outlier/COPOutlierScaling.java b/elki/src/main/java/de/lmu/ifi/dbs/elki/utilities/scaling/outlier/COPOutlierScaling.java
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+++ b/elki/src/main/java/de/lmu/ifi/dbs/elki/utilities/scaling/outlier/COPOutlierScaling.java
@@ -0,0 +1,172 @@
+package de.lmu.ifi.dbs.elki.utilities.scaling.outlier;
+
+/*
+ This file is part of ELKI:
+ Environment for Developing KDD-Applications Supported by Index-Structures
+
+ Copyright (C) 2015
+ Ludwig-Maximilians-Universität München
+ Lehr- und Forschungseinheit für Datenbanksysteme
+ ELKI Development Team
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Affero General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU Affero General Public License for more details.
+
+ You should have received a copy of the GNU Affero General Public License
+ along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+import java.util.Arrays;
+
+import de.lmu.ifi.dbs.elki.database.ids.DBIDIter;
+import de.lmu.ifi.dbs.elki.database.relation.DoubleRelation;
+import de.lmu.ifi.dbs.elki.math.statistics.distribution.Distribution;
+import de.lmu.ifi.dbs.elki.math.statistics.distribution.estimator.meta.BestFitEstimator;
+import de.lmu.ifi.dbs.elki.result.outlier.InvertedOutlierScoreMeta;
+import de.lmu.ifi.dbs.elki.result.outlier.OutlierResult;
+import de.lmu.ifi.dbs.elki.utilities.datastructures.arraylike.ArrayLikeUtil;
+import de.lmu.ifi.dbs.elki.utilities.datastructures.arraylike.NumberArrayAdapter;
+import de.lmu.ifi.dbs.elki.utilities.documentation.Reference;
+import de.lmu.ifi.dbs.elki.utilities.exceptions.AbortException;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizer;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.OptionID;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameterization.Parameterization;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameters.DoubleParameter;
+
+/**
+ * CDF based outlier score scaling.
+ * 
+ * Enhanced version of the scaling proposed in:
+ * <p>
+ * H.-P. Kriegel, P. Kröger, E. Schubert, A. Zimek<br />
+ * Interpreting and Unifying Outlier Scores<br />
+ * Proc. 11th SIAM International Conference on Data Mining (SDM), Mesa, AZ, 2011
+ * </p>
+ * 
+ * See also:
+ * <p>
+ * Hans-Peter Kriegel, Peer Kröger, Erich Schubert, Arthur Zimek<br />
+ * Outlier Detection in Arbitrarily Oriented Subspaces<br />
+ * in: Proc. IEEE International Conference on Data Mining (ICDM 2012)
+ * </p>
+ * 
+ * @author Erich Schubert
+ */
+@Reference(authors = "H.-P. Kriegel, P. Kröger, E. Schubert, A. Zimek", title = "Interpreting and Unifying Outlier Scores", booktitle = "Proc. 11th SIAM International Conference on Data Mining (SDM), Mesa, AZ, 2011", url = "http://siam.omnibooksonline.com/2011datamining/data/papers/018.pdf")
+public class COPOutlierScaling implements OutlierScalingFunction {
+  /**
+   * Phi parameter.
+   */
+  private double phi = 0.;
+
+  /**
+   * Score distribution.
+   */
+  private Distribution dist;
+
+  /**
+   * Inversion flag.
+   */
+  private boolean inverted = false;
+
+  /**
+   * Constructor.
+   * 
+   * @param phi Phi parameter
+   */
+  public COPOutlierScaling(double phi) {
+    super();
+    this.phi = phi;
+  }
+
+  /**
+   * Secondary reference.
+   */
+  @Reference(authors = "Hans-Peter Kriegel, Peer Kröger, Erich Schubert, Arthur Zimek", title = "Outlier Detection in Arbitrarily Oriented Subspaces", booktitle = "Proc. IEEE International Conference on Data Mining (ICDM 2012)")
+  public static final void secondReference() {
+    // Dummy, reference attachment point only.
+  }
+
+  @Override
+  public double getScaled(double value) {
+    if (dist == null) {
+      throw new AbortException("Programming error: outlier scaling not initialized.");
+    }
+    double s = inverted ? (1 - dist.cdf(value)) : dist.cdf(value);
+    return (phi > 0.) ? (phi * s) / (1 - s + phi) : s;
+  }
+
+  @Override
+  public double getMin() {
+    return 0.;
+  }
+
+  @Override
+  public double getMax() {
+    return 1.;
+  }
+
+  @Override
+  public void prepare(OutlierResult or) {
+    double[] s;
+    {
+      DoubleRelation scores = or.getScores();
+      s = new double[scores.size()];
+      int i = 0;
+      for (DBIDIter id = scores.iterDBIDs(); id.valid(); id.advance(), i++) {
+        s[i] = scores.doubleValue(id);
+      }
+    }
+    Arrays.sort(s);
+    dist = BestFitEstimator.STATIC.estimate(s, ArrayLikeUtil.DOUBLEARRAYADAPTER);
+    inverted = (or.getOutlierMeta() instanceof InvertedOutlierScoreMeta);
+  }
+
+  @Override
+  public <A> void prepare(A array, NumberArrayAdapter<?, A> adapter) {
+    double[] s = ArrayLikeUtil.toPrimitiveDoubleArray(array, adapter);
+    Arrays.sort(s);
+    dist = BestFitEstimator.STATIC.estimate(s, ArrayLikeUtil.DOUBLEARRAYADAPTER);
+    inverted = false; // Not supported
+  }
+
+  /**
+   * Parameterization class.
+   * 
+   * @author Erich Schubert
+   * 
+   * @apiviz.exclude
+   */
+  public static class Parameterizer extends AbstractParameterizer {
+    /**
+     * Phi parameter.
+     */
+    public static final OptionID PHI_ID = new OptionID("copscaling.phi", "Phi parameter, expected rate of outliers. Set to 0 to use raw CDF values.");
+
+    /**
+     * Phi value.
+     */
+    private double phi = 0.;
+
+    @Override
+    protected void makeOptions(Parameterization config) {
+      super.makeOptions(config);
+      DoubleParameter phiP = new DoubleParameter(PHI_ID);
+      if (config.grab(phiP)) {
+        phi = phiP.doubleValue();
+      }
+    }
+
+    @Override
+    protected COPOutlierScaling makeInstance() {
+      return new COPOutlierScaling(phi);
+    }
+  }
+}